Add eslint for `pr-checks` #7319

Job	Run time
Ruby analysis (macos-latest, default)	1m 13s
Ruby analysis (macos-latest, linked)	1m 13s
Ruby analysis (ubuntu-latest, linked)	51s
Ruby analysis (ubuntu-latest, nightly-latest)	54s
Ruby analysis (ubuntu-latest, default)	50s
Ruby analysis (macos-latest, nightly-latest)	54s
	5m 55s

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